ddd-when-to-wrap-primitives

ddd-when-to-wrap-primitives is a skill for Claude Code, Codex from amadeus-dlc/amadeus. It costs 71 tokens per session (320 once invoked), scanned A, original, Apache-2.0.

A decision guide for choosing when a string, number, or other basic value should become a named domain type.

In plain words
What is it for?
Use it when deciding whether to wrap primitives such as strings, integers, or UUIDs in value objects.
Why use it?
It helps balance the safety gained from explicit rules against the extra code and complexity of small wrapper types.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when deciding whether to wrap primitives such as strings, integers, or UUIDs in value objects.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add amadeus-dlc/amadeus --skill ddd-when-to-wrap-primitives
Clone the repo
git clone --depth 1 https://github.com/amadeus-dlc/amadeus

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for ddd-when-to-wrap-primitives

README.md
[![agentmods](https://agentmods.dev/badge/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives/github.svg)](https://agentmods.dev/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives)
Your own site
<a href="https://agentmods.dev/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives"><img src="https://agentmods.dev/badge/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for ddd-when-to-wrap-primitives

Your own site · 80×15
<a href="https://agentmods.dev/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives"><img src="https://agentmods.dev/badge/skills/amadeus-dlc/amadeus/ddd-when-to-wrap-primitives.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 71 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 320 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00071 $0.00320
Opus 5 $0.00036 $0.00160
Sonnet 5 $0.00014 $0.00064
Haiku 4.5 $0.00007 $0.00032

Measured 10d ago against content hash 94882d67c08c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

ddd-when-to-wrap-primitives scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

amadeus/spaces/default/knowledge/amadeus-shared/software-design/ddd-when-to-wrap-primitives/SKILL.md · 50 lines

What it actually says

When To Wrap Primitives

Wrap primitives when the wrapper changes correctness, not when it only signals virtue.

Wrap When

  • The value has a domain name and invariant.

  • Two values of the same primitive type can be confused.

  • Validation is repeated or easy to forget.

  • Behavior naturally belongs with the value.

  • Invalid states cause meaningful business risk.

Do Not Wrap Yet When

  • The value has no behavior or invariant.

  • The wrapper would only forward primitive operations.

  • The type is local, temporary, or purely technical.

  • The team would pay high ceremony for little safety.

Workflow

  1. List candidate primitives and their risks.

  2. Score invariant strength, misuse risk, behavior, reuse, and migration cost.

  3. Wrap the highest-value candidates first.

  4. Keep construction explicit and error reporting useful.

Detailed Reference

For non-trivial implementation, review, or refactoring work, read references/details.md before giving final guidance. It contains the detailed rules, examples, smells, and migration notes that do not belong in the short invocation body.

Output

Return a wrap/keep table with rationale and example APIs for the chosen wrappers.

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 50 lines · 71 tokens per session scan A 94882d67c08c

Subscribe to this mod's changes

ddd-when-to-wrap-primitives is a skill published in the GitHub repository amadeus-dlc/amadeus (8 stars, last pushed 19d ago), licensed Apache-2.0. It adds 71 tokens to every session and 320 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

mem0-oss-to-platform

Plan and then execute a migration of a project from the mem0 open-source / self-hosted SDK (the local Memory class) to the mem0 Platform / hosted / managed SDK (the MemoryClient class). Use this whenever a developer wants to move, switch, or migrate their mem0 usage off OSS/self-hosted to the hosted API — e.g.…

mem0ai/mem0 · 273 tokens

azure-mgmt-botservice-dotnet

Azure Resource Manager SDK for Bot Service in .NET. Management plane operations for creating and managing Azure Bot resources, channels (Teams, DirectLine, Slack), and connection settings. Triggers: "Bot Service", "BotResource", "Azure Bot", "DirectLine channel", "Teams channel", "bot management .NET", "create bot".

microsoft/skills · 78 tokens

fastapi-router-py

Create FastAPI routers with CRUD operations, authentication dependencies, and proper response models. Use when building REST API endpoints, creating new routes, implementing CRUD operations, or adding authenticated endpoints in FastAPI applications.

microsoft/skills · 46 tokens

migrate-segw-to-rap

Reverse-engineer a SEGW-built OData V2 service (MPC/DPC/MPCEXT/DPCEXT) into a modern RAP V4 service — tables, CDS views (interface + projection), behavior definitions, draft entities, service definition + binding. Use when asked to "migrate this SEGW service to RAP", "convert OData V2 to V4 RAP", "modernize this…

arc-mcp/arc-1 · 106 tokens

telnyx-messaging-hosted-curl

Set up hosted SMS numbers, toll-free verification, and RCS messaging. Use when migrating numbers or enabling rich messaging features. This skill provides REST API (curl) examples.

team-telnyx/ai · 45 tokens

common-observability

Enforce structured JSON logging, OpenTelemetry distributed tracing, and RED metrics across backend services. Use when adding request correlation, setting up tracing spans, defining SLO burn-rate alerts, or instrumenting middleware.

HoangNguyen0403/agent-skills-standard · 46 tokens